This invention relates to an apparatus and method for assembling components of elongated jewelry articles such as chains.
In the assembly of such chains, the chain is initially cut to length and end caps or D-rings are secured to the ends by welding or soldering. Subsequently a spring ring is secured to one of the ends. The spring ring has a split bail which is opened and threaded through one end of the chain and then closed. Then the bolt of the spring ring is opened, the other end of the chain is inserted in the spring ring and the bolt is allowed to close to form a closed loop of chain. These steps are normally performed by hand.
In our issued U.S. Pat. No. 4,769,884, which is hereby incorporated by reference in its entirety in this disclosure, an apparatus for automatically assembling a jewelry chain is described in detail. One of the techniques in the assembly is the opening of a spring ring by actuating the bolt and the insertion of an end cap, D-ring or quality tag of the other end of the chain and the closing of the bolt. Although the techniques described in the patent accomplished the desired result, if the orientation of the spring ring was not correct, the movement of the bolt was not always effected easily.
The present invention is an improvement of the technique of opening the bolt of a fastener, inserting an end cap, D-ring, quality tag or the like through the opened fastener and then closing the bolt. In our prior invention the robotic gripper functioned, in combination with two clamps, to accomplish the insertion. In the present invention, the clamps are modified from those disclosed in the patent and a different sequence of steps is used to accomplish the same result.
Broadly our invention comprises a first clamp configured to receive therein a fastener, a second clamp being configured to engage the latch or bolt of the fastener, a robot gripper and means to control the movement of the clamps and the gripper to effect the opening of the fastener, the insertion of the other end of the chain into the fastener and the closing of the fastener. The movement of the latch or bolt knob is coordinated with the movement of the fastener such that the forces acting on the bolt knob are substantially parallel to the direction of travel of the bolt in the fastener.
Our invention comprises a first clamp having finger-like jaws, one of said jaws configured to receive therein a spring ring and including a surface against which the bail can abut; a second clamp having finger-like jaws, one of said jaws being configured to engage the bolt knob of a spring ring, a robot gripper and means to control the movement of the clamps and the gripper.
The spring ring is acquired by the robot gripper and transferred to one clamp. The robot gripper pushes the spring ring so the bail abuts against a surface. The other clamp engages the bolt knob and both clamps moving together effect the opening of the bolt. The robot gripper holding the other end of the chain moves the fastener, such as an end cap, through the opened spring ring. The clamps rotate to close the bolt and the chain is fastened.